Mono repo -> Master (#22553)

Combines the following repositories into one:

https://github.com/mattermost/mattermost-server
https://github.com/mattermost/mattermost-webapp
https://github.com/mattermost/focalboard
https://github.com/mattermost/mattermost-plugin-playbooks

server/platform/services/remotecluster/service_test.go

@@ -0,0 +1,73 @@
+// Copyright (c) 2015-present Mattermost, Inc. All Rights Reserved.
+// See LICENSE.txt for license information.
+
+package remotecluster
+
+import (
+	"sync/atomic"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+
+	"github.com/mattermost/mattermost-server/v6/model"
+)
+
+func TestService_AddTopicListener(t *testing.T) {
+	var count int32
+
+	l1 := func(msg model.RemoteClusterMsg, rc *model.RemoteCluster, resp *Response) error {
+		atomic.AddInt32(&count, 1)
+		return nil
+	}
+	l2 := func(msg model.RemoteClusterMsg, rc *model.RemoteCluster, resp *Response) error {
+		atomic.AddInt32(&count, 1)
+		return nil
+	}
+	l3 := func(msg model.RemoteClusterMsg, rc *model.RemoteCluster, resp *Response) error {
+		atomic.AddInt32(&count, 1)
+		return nil
+	}
+
+	mockServer := newMockServer(makeRemoteClusters(NumRemotes, ""))
+	defer mockServer.Shutdown()
+
+	service, err := NewRemoteClusterService(mockServer)
+	require.NoError(t, err)
+
+	l1id := service.AddTopicListener("test", l1)
+	l2id := service.AddTopicListener("test", l2)
+	l3id := service.AddTopicListener("different", l3)
+
+	listeners := service.getTopicListeners("test")
+	assert.Len(t, listeners, 2)
+
+	rc := &model.RemoteCluster{}
+	msg1 := model.RemoteClusterMsg{Topic: "test"}
+	msg2 := model.RemoteClusterMsg{Topic: "different"}
+
+	service.ReceiveIncomingMsg(rc, msg1)
+	assert.Equal(t, int32(2), atomic.LoadInt32(&count))
+
+	service.ReceiveIncomingMsg(rc, msg2)
+	assert.Equal(t, int32(3), atomic.LoadInt32(&count))
+
+	service.RemoveTopicListener(l1id)
+	service.ReceiveIncomingMsg(rc, msg1)
+	assert.Equal(t, int32(4), atomic.LoadInt32(&count))
+
+	service.RemoveTopicListener(l2id)
+	service.ReceiveIncomingMsg(rc, msg1)
+	assert.Equal(t, int32(4), atomic.LoadInt32(&count))
+
+	service.ReceiveIncomingMsg(rc, msg2)
+	assert.Equal(t, int32(5), atomic.LoadInt32(&count))
+
+	service.RemoveTopicListener(l3id)
+	service.ReceiveIncomingMsg(rc, msg1)
+	service.ReceiveIncomingMsg(rc, msg2)
+	assert.Equal(t, int32(5), atomic.LoadInt32(&count))
+
+	listeners = service.getTopicListeners("test")
+	assert.Empty(t, listeners)
+}